Telnet is a protocol allowing you to connect to a remote system and run programs and commands on that system. It is very old and still very much in use today.

Unfortunately, Telnet, by default, does not encrypt any data sent over the connection (including passwords), and so it is often practical to eavesdrop on the communications and use the password later for malicious purposes; anybody who has access to a router, switch, hub or gateway located on the network between the two hosts where Telnet is being used can intercept the packets passing by and obtain login and password information (and whatever else is typed) with any of several common utilities like tcpdump and Wireshark.

On the other hand, a program called ssh exists that can replace both telnet and ftp in a secure, encrypted way.

Ssh stands for Secure Shell. It will encrypt each connection with a random key, so that it is impossible or at least very hard for a third party to decrypt the connection and find the password, or spy on you.

Use putty (Here) if you are on windows or use "ssh" command (example shown below) from Linux/UNIX box to connect to the remote server.

# ssh 192.168.0.2
The authenticity of host '192.168.0.2 (192.168.0.2)' can't be established.
RSA key fingerprint is 2b:91:9b:c1:a7:57:91:dc:93:b3:04:50:c0:b9:bd:ba.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '192.168.0.2' (RSA) to the list of known hosts.
Password: